Detection and Characterization of Malathion Adherence to Piping Materials Used in Water Distribution Systems
Abstract
Protection of the public water supply is a national security priority, and as such, it is important to better understand the fate of a chemical weapons agent injection into a public water distribution system. This study investigated the adherence of malathion to pipe materials that are used in public water distribution systems, with malathion serving as a chemical representative of the organophosphorus nerve agent VX. Copper and iron specimen were exposed to malathion solutions for periods of 4, 8, and 24 hours and then tested for evidence of chemical adherence to the metal surfaces. Nonlinear desiccation profiles revealed total mass losses that were typically between 0.01-0.02% but notable mass increases were also observed during desiccation, likely due to surface reactions involving oxygen. Normalized mass differences were poorly correlated with the malathion concentrations (R2 typically < 0.6), which suggests that mass-based measurements are not sufficient to determine malathion exposure to pipe materials. X-ray photoelectron spectroscopy was also used in an effort to detect shifts in the adsorptive spectra that appeared to be attributable to the presence of trace levels of malathion on the surface of the exposed pipe materials. The spectra observed from the XPS analysis of the copper and iron specimen suggests that the presence of malathion on the surface of the pipe material can sufficiently be detected and measured by XPS analysis. To the author's knowledge, this the first study to investigate malathion adherence to pipe materials with mass measurements and XPS."
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 26, 2015
- Accession Number
- ADA615406
Entities
People
- William D. Flemings
Organizations
- Air Force Institute of Technology